In northern climates, it is common practice to sprinkle quantities of sand or other aggregates including certain chemicals onto roadway surfaces after winter time storms to render the ice on the road surface less slippery and to melt the ice for removal.
It has been conventional to mount a distributing device on the tailgate end of the box of a dump truck so that the sand or aggregate may be distributed over an area of the road surface behind the truck.
However, many of the modern streets and highways are four lanes wide with two lanes going in each direction, and in addition, there is often an additional left turn lane near the center of the roadway, and an additional right turn lane adjacent the right or outside edge of the roadway. It has been found that the distributing equipment previously available for use on the tailgate end of a box on a dump truck is inadequate for obtaining the proper spreading of sand and gravel across the entire width of the usable roadway surfaces.